Fanconi anemia complementation group A cells are hypertensive to chromium(VI)-induced toxicity

Document Type

Journal Article

Publication Date

1-1-2002

Journal

Environmental Health Perspectives

Volume

110

Issue

SUPPL. 5

DOI

10.1289/ehp.02110s5773

Keywords

Apoptosis; Carcinogen; Caspase-3; Clonogenicity; DNA adducts; Genotoxin; Phosphatidylserine translocation; Sodium chromate; Uptake

Abstract

Fanconi anemia (FA) is an autosomal recessive disorder characterized by diverse developmental abnormalities, progressive bone marrow failure, and a markedly increased incidence of malignancy. FA cells are hypersensitive to DNA cross-linking agents, suggesting a general defect in the repair of DNA cross-links. Some forms of hexavalent chromium [Cr(VI)] are implicated as respiratory carcinogens and induce several types of DNA lesions, including ternary DNA-Cr-DNA interstrand cross-links (Cr-DDC). We hypothesized that human FA complementation group A (FA-A) cells would be hypersensitive to Cr(VI) and Cr(VI)-induces apoptosis. Using phosphatidylserine translocation and caspase-3 activation, human FA-A fibroblasts were found to be markedly hypersensitive to chromium-induced apptosis compared with CRL-1634 cells, which are normal human foreskin fibroblasts (CRL). The clonogenicity of FA-A cells was also significantly decreased compared with CRL cells after Cr(VI) treatment. There was no significant difference in either Cr(VI) uptake or Cr-DNA adduct formation between FA-A and CRL cells. These results show that FA-A cells are hupersensitive to Cr(VI) and Cr-incuced apoptosis and that this hupersensitivity is not due to increased Cr(VI) uptake or increased Cr-DNA adduct formation. The results also suggest that Cr-DDC may be proapoptotic lesions. These results are the first to show that FA cells are hypersensitive to an environmentally relevant DNA cross-linking agent.

This document is currently not available here.

Share

COinS